The Food and Drug Administration (FDA) has approved Vanflyta® (quizartinib) in combination with standard cytarabine and anthracycline induction and cytarabine consolidation, and as maintenance monotherapy following consolidation chemotherapy, for the treatment of adults with newly diagnosed acute myeloid leukemia (AML) that is FLT3 internal tandem duplication (ITD)-positive as detected by an FDA-approved test.
Quizartinib is an oral, highly potent type II FLT3 inhibitor that selectively targets FLT3-ITD mutations. The approval was based on data from the phase 3 QuANTUM First study (ClinicalTrials.gov Identifier: NCT02668653), which compared the efficacy and safety of quizartinib to placebo in combination with standard cytarabine and anthracycline induction and standard cytarabine consolidation chemotherapy, and then as continued single agent therapy, in adults with newly diagnosed AML that is FLT3-ITD positive.
Findings showed a 22% reduction in the risk of death with quizartinib compared with chemotherapy alone (hazard ratio [HR], 0.78; 95% CI, 0.62-0.98; 2-sided P =.0324). In the quizartinib arm, the complete remission (CR) rate was 55% (95% CI, 48.7-60.9) with a median duration of CR of 38.6 months (95% CI, 21.9-NE). In the placebo arm, the CR rate was 55% (95% CI, 49.2-61.4) with a median duration of CR of 12.4 months (95% CI, 8.8-22.7).
In an exploratory subgroup analysis of patients who received maintenance therapy with quizartinib or placebo following consolidation chemotherapy (n=89/208), the overall survival (OS) HR was 0.40 (95% CI, 0.19-0.84). Among patients who received maintenance therapy with quizartinib or placebo following allogeneic hematopoietic stem cell transplantation (HSCT) (n=119/208), the OS HR was 1.62 (95% CI, 0.62-4.22).
The most common adverse reactions reported with quizartinib were decreased lymphocytes, decreased potassium, decreased albumin, decreased phosphorus, increased alkaline phosphatase, decreased magnesium, febrile neutropenia, diarrhea, mucositis, nausea, decreased calcium, abdominal pain, sepsis, neutropenia, headache, increased creatine phosphokinase, vomiting, and upper respiratory tract infection.
The prescribing information for Vanflyta includes a Boxed Warning regarding the risk of QT prolongation, torsades de pointes, and cardiac arrest. Vanflyta is available only through a restricted program under a Risk Evaluation and Mitigation Strategy (REMS) called the Vanflyta REMS.
Vanflyta is supplied as tablets in 17.7mg and 26.5 mg dosage strengths. The product is expected to be available in the coming weeks.
The FDA has also approved the LeukoStrat CDx FLT3 Mutation Assay as a companion diagnostic for Vanflyta.
This article originally appeared on MPR